Getting active uploaders from Panopto

SELECT distinct replace(replace(replace([UserName],'blackboard\',''),'-ac',''),'pau.local\','') as UserName
FROM
(
SELECT [UserName]
,DATEADD(ms,
((cast((startTime*10000000) as BIGINT)) / CAST(10000 AS bigint)) % 86400000,
DATEADD(day, (cast((startTime*10000000) as BIGINT)) / CAST(864000000000 AS bigint) - 109207, 0)) AS realStartTime
FROM [PanoptoDB_3].[dbo].[activityLog]
JOIN [PanoptoDB_3].[dbo].[aspnet_Users] ON [PanoptoDB_3].[dbo].[aspnet_Users].[UserId] = [PanoptoDB_3].[dbo].[activityLog].[userID]
WHERE [PanoptoDB_3].[dbo].[activityLog].[action] > 0
AND [PanoptoDB_3].[dbo].[activityLog].[SessionId] is not null
) AS t
WHERE realStartTime > '2013-09-01'
order by UserName